CN100571610C - Pressure measurement method, pressure gauge and tonometer - Google Patents
Pressure measurement method, pressure gauge and tonometer Download PDFInfo
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- CN100571610C CN100571610C CNB2005800126070A CN200580012607A CN100571610C CN 100571610 C CN100571610 C CN 100571610C CN B2005800126070 A CNB2005800126070 A CN B2005800126070A CN 200580012607 A CN200580012607 A CN 200580012607A CN 100571610 C CN100571610 C CN 100571610C
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0001—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means
- G01L9/0008—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means using vibrations
- G01L9/0022—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means using vibrations of a piezoelectric element
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
- A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
- A61B3/16—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for measuring intraocular pressure, e.g. tonometers
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/0048—Detecting, measuring or recording by applying mechanical forces or stimuli
- A61B5/0051—Detecting, measuring or recording by applying mechanical forces or stimuli by applying vibrations
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L11/00—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
- G01L9/008—Transmitting or indicating the displacement of flexible diaphragms using piezoelectric devices
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Abstract
The invention provides a kind of pressure measurement method and a kind of measure of intraocular pressure device, in this pressure measurement method with simple method and with the high performance reproducibility gaging pressure, this measure of intraocular pressure device can be measured intraocular pressure by only contacting with eyelid, and subjects oneself can carry out measure of intraocular pressure.Described measure of intraocular pressure device comprises measuring device (1), piezoelectric actuator, terminal pedestal, information processor and resistor.Measuring device (1) comprise vibrator (11) such as bimorph type vibrator, four rubber earring mouldings (12), can be with the vibrator (11) and the shell (13) of rubber earring moulding (12) vibration and the catalyst (14) that contacts with eyelid (16) that are contained in wherein.Press in the measurement within the eye, catalyst (14) contacts with eyelid (16).Construct vibrator (11) by bimorph type vibrator, wherein electric current according to intrinsic pressure change of the contacted measurand of this vibrator, this vibrator has the constant AC voltage that is applied on it.Measure pressure by measuring in this vibrator value of current flowing such as the intraocular pressure of measurand.
Description
Technical field
The present invention relates to a kind of pressure measurement method, pressure gauge and tonometer, it is particularly suitable for being applied to the measure of intraocular pressure technology that is used for ophthalmologic examination.
Background technology
Following two kinds of methods are considered to the measure of intraocular pressure method usually.Specifically, adopt a kind of method that predetermined pressure is applied on the cornea, so that measure intraocular pressure based on the pressured state that causes by pressure of cornea; Adopt a kind of method of estimating intraocular pressure in addition, this is by making prelum contact cornea (being contact-type), perhaps by the corneal blowing compressed air and based on made the area ratio of corneal distortion estimate intraocular pressure by air pressure.
Yet in these methods, cornea directly is upset, thereby requires to have high safety grade.In addition, tested personnel must bear bigger burden, all if necessary local anesthesia or the uncomfortable sensation caused by blowing.
Therefore, in order to address these problems, the whole bag of tricks has been proposed.For instance, the example of the method that is proposed comprises: (see JP02-180241A, US 5,375,595 and US 5 with the acoustic vibration eyeball surface and based on the method that the surperficial wave propagation velocity of the resonant frequency of Oscillation Amplitude, eyeball or eyeball is measured intraocular pressure, 251,627); And under closed-eye state, push eyeball so that measure the method (seeing JP06-105811A, JP08-280630A and JP 08-322803A) of intraocular pressure by eyelid.
DISCLOSURE OF INVENTION
Problem solved by the invention
Yet, above-mentioned traditional pressure measurement method and have following point as the tonometer of its device.That is to say that the method that makes prelum directly contact cornea need be anaesthetized or similar processing and cause the examinee to feel uncomfortable or pain.
JP 02-180241A, US 5,375,595 and US 5,251, the method described in 627 is also because measure of intraocular pressure is to carry out under the state of opening eyes and cause the examinee to feel uncomfortable or pain.The size of pressure gauge own stimulates cornea more greatly and directly, thereby requires high safety grade.Therefore, the examiner must be doctor or medical personnel.
The state (being closed-eye state) that JP06-105811A, JP 08-280630A and JP 08-322803A disclose at catacleisis is carried out the method for checking down.According to the present inventor's discovery, use the result that measure of intraocular pressure obtained repeatable not enough of this method.
Therefore, needing day by day to develop can gaging pressure (for example intraocular pressure) and do not cause the examinee to feel under the weather or the technology of pain, and can be by the technology of examinee with high performance reproducibility gaging pressure (for example intraocular pressure).
Like this, an object of the present invention is to provide the method for the enough simple metering systems of a kind of energy with the high performance reproducibility gaging pressure, and provide a kind of pressure gauge, when this pressure gauge is applied to measure of intraocular pressure device (tonometer), this pressure gauge can be measured intraocular pressure by only taking place slightly to contact with eyelid, it is by simple method gaging pressure and the examinee is felt under the weather or pain accurately, and measures intraocular pressure by the examinee.
The measure that is used to deal with problems
In order to solve the problems referred to above in the conventional art, the present inventor has carried out the research of concentrating, and is summarized as follows.
According to the present inventor's discovery, in above-mentioned conventional art, press the load that is applied to cornea during measuring to cause uncomfortable feeling within the eye.Therefore, the present inventor has studied under the state of catacleisis and to have implemented measure of intraocular pressure and non-corneal applies the method for load.
As the result of research, the present inventor proposes to use vibrator.That is to say, as various experiments with based on the result of the research of described experiment, the present inventor finds a feature: when predetermined alternating voltage be applied to vibrator (for example bimorph type vibrator) in case Continuous Drive it the time, the electric current of this vibrator of flowing through is corresponding to changing with the contacted material of this vibrator.As further experiment with based on the result of the research of this discovery, the present inventor sums up: when eyeball was vibrated by vibrator, the electric current of this vibrator of flowing through changed according to intraocular pressure, thereby can measure intraocular pressure by the current value measurement.
The present invention is based on above-mentioned research and derives.
The invention is characterized in and used a kind of pressure gauge, wherein vibrating device can contact with measurand directly or indirectly, apply voltage so that this vibrating device vibrates with measurand to this vibrating device, the current value that measurement changes according to the Oscillation Amplitude of this vibrating device, and calculate the pressure of measurand based on measured current value.
Specifically, first aspect of the present invention provides a kind of pressure measurement method, comprising:
Make vibrating device contact with measurand by contact device, this vibrating device is connected to this contact device so that contact with measurand and vibrated by applying voltage, and wherein this measurand has predetermined shape and exerts pressure at outward direction from this measurand;
Apply voltage for this vibrating device by voltage bringing device, this voltage bringing device is used for alternating voltage is applied to this vibrating device;
Flow through the current value of this vibrating device by the measuring device measurement, this measuring device is used to measure the current value that flows through this vibrating device; And
Come calculating pressure based on measured current value.
According to a first aspect of the invention, under typical situation, variation based on the described current value that is caused by vibration frequency change is calculated the resonance point of measurand by information processor, and measures the pressure based on the current value in the zone of this resonance point.
Of the present invention aspect first in, be suitable for using tested references object to be used as the reference that the correcting measuring value changes, this measurement variation is that the temperature characterisitic by described vibrator causes, before measurand is carried out pressure measxurement or basically with, side by side tested references object is carried out pressure measxurement, and the measured value of the measured value of tested references object and measurand is compared so that measure the pressure of measurand measurand execution pressure measxurement.
Second aspect of the present invention provides a kind of pressure gauge, comprising:
Be used for and the contacted contact device of measurand, wherein this measurand has predetermined shape and exerts pressure at outward direction from this measurand;
Vibrating device, it is connected with this contact device and is vibrated by applying voltage;
Voltage bringing device, it is used for applying alternating voltage to this vibrating device;
Measuring device, it is used to measure the current value that flows through this vibrating device; And
Information processor, it is used to calculate the force value corresponding to by the measured current value of this measuring device,
Wherein, when this alternating voltage being applied to this vibrating device this vibrating device contacts with this measurand by this contact device simultaneously by this voltage bringing device, flow through this current value of this vibrating device by this measuring device measurement, and calculate the pressure of this measurand by this information processor.
The 3rd aspect of the present invention provides a kind of tonometer, comprising:
Contact device, it is used for and the eyeball mediate contact;
Vibrating device, it is connected with this contact device and is vibrated by applying voltage;
Voltage bringing device, it is used for applying alternating voltage to this vibrating device;
Measuring device, it is used to measure the current value that flows through this vibrating device; And
Information processor, it is used to calculate the force value corresponding to by this measured current value of this measuring device, wherein, when this alternating voltage being applied to this vibrating device this vibrating device contacts with eyeball by this contact device simultaneously by this voltage bringing device, flow through this current value of this vibrating device by this measuring device measurement, and calculate the intraocular pressure of eyeball by this information processor.
In aspect of the present invention second and the 3rd, under typical situation, calculate the resonance point of measurand, and measure the current value in the zone of this resonance point based on the variation of the measured current value that causes by vibration frequency change.
In aspect of the present invention second and the 3rd, under typical situation, further at the outer setting bracing or strutting arrangement of the moving area of the moving area of described contact device and described vibrating device.
In aspect of the present invention second and the 3rd, be suitable for adopting a kind of like this structure, wherein, before measurand is carried out pressure measxurement or measure of intraocular pressure, tested references object is carried out pressure measxurement with as the reference that is used for the variation of correcting measuring value, this measurement variation is that the temperature characterisitic by described vibrator causes, and by described accountant the measured value of the measured value of tested references object and measurand is compared so that measure the pressure of measurand.
In aspect of the present invention second and the 3rd, be suitable for further comprising that output device is to be used to export result who is obtained by described measuring device and/or the result who is obtained by described accountant.In the present invention, described contact device typically is connected with vibrating device by retaining element.Expectation uses elasticity entity (for example rubber) to be used as this retaining element.
Technological thought of the present invention is not necessarily limited to combinations thereof.Like this, also comprise the technological thought that any appropriate combination realized by above-mentioned many aspects of the present invention.
Effect of the present invention
As mentioned above, according to pressure measurement method of the present invention, can be by the pressure of simple method with high performance reproducibility measurement measurand, this measurand has reservation shape and outwards exerts pressure from this measurand.
According in the middle of pressure gauge of the present invention and the tonometer each, can be only slightly contact internal pressure or the intraocular pressure of measuring the shape that is used to keep measurand by eyelid and measurand or eyeball.Therefore, can accurately measure described pressure and can not produce big influence by simple method measurand.
According to tonometer of the present invention, can accurately measure intraocular pressure and can not exert an influence by simple method to eyeball.Therefore, can accurately measure intraocular pressure safely and the examinee is felt under the weather by the examinee.
The accompanying drawing summary
Fig. 1 shows the diagram of pressure gauge according to an embodiment of the invention;
Fig. 2 shows the sketch map of the measuring device that is used for measure of intraocular pressure in an embodiment of the present invention;
Fig. 3 A shows the sketch map of the bimorph type vibrator that is included in an embodiment of the present invention in the described measuring device;
Fig. 3 B shows the sketch map of the bimorph type vibrator that is included in an embodiment of the present invention in the described measuring device;
Fig. 4 A shows the diagram of vibrator equivalent circuit in an embodiment of the present invention;
Fig. 4 B is the frequency-impedance operator of vibrator in an embodiment of the present invention;
Fig. 5 A shows the curve chart that utilizes measure of intraocular pressure method according to an embodiment of the invention, frequency-current characteristics result that the internal pressure of the balloon of water obtains is housed by change;
Fig. 5 B shows the curve chart that utilizes measure of intraocular pressure method according to an embodiment of the invention, frequency-current characteristics result that the internal pressure of the balloon of water obtains is housed by change;
Fig. 6 A shows under the state that in an embodiment of the present invention measuring device directly contacts Oculus sus domestica, by measuring the result's that intraocular pressure obtains curve chart;
Fig. 6 B shows under the state that in an embodiment of the present invention measuring device directly contacts Oculus sus domestica, by measuring the result's that intraocular pressure obtains curve chart;
Fig. 7 A shows under in an embodiment of the present invention the state of measuring device by eyelid contact Oculus sus domestica, by measuring the result's that intraocular pressure obtains curve chart;
Fig. 7 B shows under in an embodiment of the present invention the state of measuring device by eyelid contact Oculus sus domestica, by measuring the result's that intraocular pressure obtains curve chart;
The result's that Fig. 8 shows under the situation that in an embodiment of the present invention measuring device directly contacts Oculus sus domestica and under the situation of this measuring device by eyelid contact Oculus sus domestica, obtain by the current-to-pressure feature measurement curve chart;
Fig. 9 A shows measuring device in utilizing embodiments of the invention and same examinee is carried out the curve chart of measuring the result who obtains under the situation of 10 measure of intraocular pressure, by frequency-current characteristics;
Fig. 9 B shows measuring device in utilizing embodiments of the invention and same examinee is carried out the curve chart of measuring the result who obtains under the situation of 10 measure of intraocular pressure, by frequency-current characteristics;
Figure 10 is a sketch map of explaining the calibration steps of the measure of intraocular pressure that is used for embodiments of the invention;
Figure 11 shows under the situation that measuring device in using embodiments of the invention and traditional Puffer type tonometer measure people's intraocular pressure, by measuring the curve chart of the results change that obtains;
Figure 12 shows the sketch map of the measuring device that is equipped with supporting base in an embodiment of the present invention; And
Figure 13 shows the sketch map of the measuring device that is equipped with supporting base in an embodiment of the present invention.
Preferred forms of the present invention
Embodiments of the invention are described below with reference to accompanying drawings.Should be noted that corresponding to the identical or appropriate section in each accompanying drawing of the following example and represent with identical Reference numeral.
Pressure gauge is according to an embodiment of the invention at first described.Fig. 1 shows the overall structure according to the pressure gauge of this embodiment.
As shown in Figure 1, pressure gauge is used as the tonometer use according to an embodiment of the invention, and it comprises measuring device 1, piezoelectric actuator 2, terminal pedestal 3, information processor 4 and the resistor 5 that is used for the actual measurement intraocular pressure.
Use this piezoelectric actuator 2 to amplify the voltage that is applied.Terminal pedestal 3 is used to concentrate the input and output distribution, the voltage that is amplified by piezoelectric actuator 2 is applied to measuring device 1 with as output, and measures electromotive force or the voltage that conduct is imported.Should be noted that piezoelectric actuator 2 is constructed such that the voltage of exporting from terminal pedestal 3 can be exaggerated for example 15 times.Use resistor 5 so that produce voltage drop between two ends of resistor 5, its resistance value is for example 1k Ω in this embodiment.
Included auxiliary storage part (not shown) has operating system (OS) 4a (it serves as the basis), information stored data base 4b, measurement result processing application 4c, input data analysis program 4d, computing application 4e and the outlet side frequency shift program 4f that is used for operation information blood processor 4 in information processor 4, and these all are installed in wherein.Information processor 4 is carried out multiple analyzing and processing and computing based on described program.In the example that is described below, carry out measurement based on described program and handle and analyzing and processing.
(measuring device)
Next use description to measuring device 1 according to the pressure gauge of this embodiment.Fig. 2 illustrates measuring device 1, and Fig. 3 illustrates an example of the bimorph type vibrator that is used for measuring device 1.
As shown in Figure 2, have according to the measuring device 1 of this embodiment and make catalyst 14 and eyelid 16 contacted structures during being used for pressing within the eye measurement.Measuring device 1 comprise as the vibrator 11 (for example bimorph type vibrator) of vibrating device, four rubber earring mouldings 12 as the elasticity entity, can be with covering on the vibrator 11 and the shell 13 of rubber earring moulding 12 vibrations wherein and being used for catalyst 14 with eyelid 16 actual contact.Therefore, vibrator 11 contacts with eyeball 17 basically indirectly, thereby makes eyeball 17 with vibrator 11 vibrations.
By two pairs of rubber earring mouldings 12 in both sides fixing vibrator 11, thereby make its location and be fixed on the center of shell 13.As shown in Figure 3, vibrator 11 has such structure: metallic plate 11b is clipped in the centre of ceramic component 11a.Vibrator 11 is electrically connected (not shown in Fig. 3) by vibrator cable 15 with piezoelectric actuator 2.
In the measuring device 1 with said structure, when applying voltage to vibrator 11 by vibrator cable 15 from the outside, vibrator 11 at first vibrates.Then, rubber earring moulding 12, shell 13 and catalyst 14 are passed through in described vibration, thereby make whole casing 13 vibrations so that by catalyst 14 and eyelid 16 described vibration is sent to eyeball 17.That is to say that the measuring device 1 among this embodiment is used to provide vibration to tested eyeball, and do not have the vibration of measuring tested eyeball intrusively.Should be noted that " do not have and invade " bright element that does not use the cornea (not specifically illustrating) of direct contact eyeball 17 of a vocabulary.
(measure of intraocular pressure principle)
The measuring principle of using the pressure gauge with said structure to measure intraocular pressure will be described below.
Result as experiment and concentrated research, the present inventor finds that the vibrator 11 provide has following feature in measuring device 1: when applying predetermined alternating voltage when driving this vibrator continuously, the electric current of this vibrator of flowing through changes corresponding to the state of measurand, and this measurand contacts with vibrator 11 by catalyst 14.Will be described below experiment and research for the bimorph type vibrator that is used as vibrator 11.
(bimorph type vibrator)
Shown in Fig. 4 B, vibrator 11 parallel resonance and its impedance change according to the frequency of the voltage that is applied.Therefore, clearly, when the alternating voltage that is applied was remained on predetermined voltage continuously, the electric current of this vibrator 11 of flowing through changed according to frequency.In Fig. 4 B, be the mechanical resonance point of vibrator 11 as the fs of one of resonance point, be the resonance point that causes by vibrator 11 as the fp of another resonance point.
The measuring device 1 of involving vibrations device 11 is placed on the rubber vibration isolator (not shown).Other vibrator cables etc. are set.After this, under each measuring frequency, use laser irradiation vibrator 11, so that utilize laser displacement gauge to measure its Oscillation Amplitude.With the interval of 10Hz the frequency configuration of the voltage that is applied to 400Hz to 700Hz.With described measuring frequency be set to predetermined resonance point near, more particularly, it is arranged in the frequency range near this resonance point.
As measurement result, find that eigenvalue and resonant frequency are offset according to the hardness of material.As mentioned above, vibrator 11 parallel resonance and its impedance change according to the frequency of the voltage that is applied.That is to say that when the alternating voltage that is applied was remained on predetermined voltage continuously, the electric current that is flow through changed according to frequency.Therefore, this feature is utilized.From the flow through electric current of vibrator 11 of the voltage drop measurement at resistor 5 two ends that are connected in series with vibrator 11.Calculate intraocular pressure based on measured current value.
(measure of intraocular pressure method)
Specifically, at first measuring device 1 is arranged to contact with eyeball 17 by eyelid 16.Next, according to the frequency change program that is installed in the information processor 4 alternating voltage is applied to vibrator 11.When this vibrator 11 vibrates owing to applying of this alternating voltage, whole measuring device 1 vibration.This vibration is sent to eyeball 17 by eyelid 16.When this vibration was sent to eyeball 17, eyeball 17 also produced the vibration corresponding to its intraocular pressure, thereby changed the Oscillation Amplitude of measuring device 1.Therefore, the amplitude of vibrator 11 changes, and the electric current of the vibrator 11 of flowing through changes owing to the variation of its amplitude.
Then, the electromotive force at measurement resistor 5 two ends, and measured potential value is input to information processor 4.Information processor 4 is used based on described computing described potential value is carried out computing, so that obtain difference (being voltage) therebetween.Therefore, calculate the variation of the electric current of the vibrator 11 of flowing through.Calculate the intraocular pressure value by information processor 4 based on described current value.Because information processor 4 comprises the display as output device, therefore when the described electric current of calculating changes, the result that analyzing and processing obtained of operational analysis program is presented on this display.
Though below with reference to example specific implementation ad hoc approach of the present invention is described, the invention is not restricted to these methods.
Example 1
The rubber balloon that water is housed is attached to an end of cylindrical glass tube as the model of eyeball.This cylindrical glass tube is fixed on the supporting base.The catalyst 14 of measuring device 1 contacts with this balloon, and water slowly is injected in this glass tubing to change the intrinsic pressure of this balloon.At this moment, the level that increases 1cm from the interface portion between balloon and the glass tubing is made as reference.Interval with 5cm is increased to 5cm, 10cm and 15cm to described level from this reference, so that change the intrinsic pressure of balloon.Fig. 5 shows by measuring the result's that obtains frequency characteristic, and Fig. 5 B shows the amplified curve figure in the resonance point zone in the frequency range shown in Fig. 5 A.
As seen from Figure 5, when measuring device 1 contacts with rubber balloon when measuring, can obtain current characteristics according to the order of pressure, and the resonance point of vibrator 11 is present in 700Hz in the frequency field of 850Hz.Also can be as seen from the figure, in the frequency range outside the frequency field between two resonance points, along with the increase of pressure, current characteristics reduces.In contrast, in the frequency field between two resonance points, along with the increase of pressure, current characteristics increases.Therefrom as can be seen, under the situation of mechanical resonance, along with the intrinsic pressure increase of balloon, electric current reduces.Under the situation based on the resonance of electric capacity, along with the increase of pressure, electric current increases.Therefrom as can be seen, when intrinsic pressure change, can use measuring device 1 to determine the pressure that changes.
Example 2
Next, under the situation of the intrinsic pressure change of its eyeball, measure the frequency-current characteristics of the eyeball that has eyelid (Oculus sus domestica that has eyelid) of pig.The method that the intraocular pressure that adopts changes is a kind of like this method: insert injection needle from the optic nerve of Oculus sus domestica, this injection needle is linked to each other with the container that comprises the normal-salt aqueous solution, and this container is moved up and down so that the horizontal plane of this container equals the level of Oculus sus domestica substantially, thereby the intraocular pressure of change pig.Then, open the eyelid of the Oculus sus domestica that has eyelid, and make directly contact eyeball of measuring device 1.Implement to measure in the frequency field of 850Hz at 700Hz.After this, close eyelid and implement identical measurement in contact with eyelid.When changing intraocular pressure, repeat above-mentioned a series of measurement.
Measure the result that obtained shown in Fig. 6 and 7 by aforesaid frequency-current characteristics.Fig. 6 is illustrated in the directly result that measurement obtained under the situation of contact eyeball of measuring device 1.Fig. 7 is illustrated in the result that measurement obtained under the situation of measuring device 1 contact eyelid under the state of catacleisis.Fig. 6 B and 7B show the amplified curve figure in the resonance point zone in the frequency range shown in Fig. 6 A and the 7A.
From Fig. 6 and 7, find out, can contact under every kind of situation of eyelid order acquisition current characteristics with measuring device 1 at measuring device 1 contact eyeball according to pressure.In addition, the result under the situation of measuring device 1 contact eyeball is closely similar with the result under the situation that contacts eyelid at measuring device 1.
Based on described result, Fig. 8 shows the comparison between the result of the result of Fig. 6 and Fig. 7 about the dependency at current value under the Frequency point of 769Hz (it is at the intermediate point between local maximum point and the local smallest point (i.e. two resonance points)) and pressure.
As can be seen from Figure 8, produced current offset, obtained similar characteristic though contact with measuring device 1 in the situation of measuring device 1 contact eyeball between the situation of eyelid.Therefore, to be used under the situation among this embodiment at measuring device 1 be very little in the influence that it is apparent that eyelid 16.
Example 3
In the process that Oculus sus domestica is measured, the present inventor finds that the vibrator 11 of measuring device 1 has temperature characterisitic, and has changed electric current thus.Then, the present inventor has imagined a kind of method of implementing measurement in vibrator 11 sustained vibrations after its filament saturation.Therefore, can carry out stable measure of intraocular pressure.
Adopt this method, and use measuring device 1 to carry out current characteristics continuously and measure for same examinee.That is to say vibrator 11 vibrations 45 minutes.After the filament saturation of vibrator 11, make the eyelid of the measuring device 1 contact people among this embodiment at once, and under 2 minutes interval, carry out 10 primary current feature measurements.The frequency field of measuring corresponding to current characteristics is set to 700Hz to 840Hz.Measuring device 1 all separates with eyelid 16 for each measurement.Fig. 9 illustrates the result that measurement obtains.Fig. 9 B shows the amplified curve figure in the resonance point zone in the frequency range shown in Fig. 9 A.
As can be seen from Figure 9, along with the increase of the measurement quantity in the frequency range of the frequency field outside between two resonance points, electric current increases.It is evident that from the result of above-mentioned example 1 electric current in the frequency range of the frequency field outside between two resonance points increases and is equivalent to reducing of measured pressure.What therefore, it is apparent that measurement repeats to have changed intraocular pressure.
Example 4
For above-mentioned current characteristics measure adopted make vibrator 11 vibrations up to the method for its filament saturation spended time too.Its reason is that vibrator 11 has temperature characterisitic.So as the result of study for the method that minimizes the temperature characterisitic influence, the present inventor dreams up a kind of use and carries out Calibration Method with reference to pedestal.Figure 10 shows and uses this calibration procedure with reference to pedestal.
As shown in figure 10, make by for example rubber, and be placed on and have on the identical elastic spring 22 of the situation of being pressed with eyeball with reference to pedestal 21.The catalyst 14 of measuring device 1 contacts with the top with reference to pedestal 21, measures so that carry out.The catalyst 14 of measuring device 1 is contacted with eyelid 16 after this, so that measure intraocular pressure at once.That is to say, carry out simultaneously basically for reference pedestal 21 (to continue to keep predetermined pressure) measurement and for measurement as the tested eyeball of checked object.Specifically, described measurement is one in front and one in back carried out in succession.Therefore, based on use the value that records with reference to pedestal 21 at the contact eyelid so that in order to obtain intraocular pressure under the situation of execution analysis measured value calibrate so that improve the precision of measuring.
Specifically, with respect to the value " x " that under the situation of catalyst 14 contacts, is obtained, under each frequency, use following expression (1) to calculate in the gain alpha of the following value of obtaining of situation " y " that contacts eyelid with reference to pedestal 21.
α＝y/x (1)
Gain alpha in expression formula (1) is to be applied to continuously with reference to the ratio of the predetermined pressure on the pedestal 21 with the pressure that records from eyelid 16.Be applied to reference to the pressure on the pedestal 21 and be held constant, constant thereby measured pressure becomes.Therefore, the intraocular pressure value that records from eyelid 16 can accurately obtain based on gain alpha.Measurement for reference pedestal 21 is carried out basically simultaneously with the measurement for eyelid 16, thereby the influence of temperature characterisitic can be reduced to minimum.
Example 5
Based on above-mentioned calibration, implement measure of intraocular pressure under the present inventor's measuring device 1 in this embodiment and people's the eyelid state of contact.Example as a comparison, the present inventor uses traditional Puffer type tonometer that people's eyeball is implemented measure of intraocular pressure.Figure 11 illustrates the result that measurement obtains.As shown in figure 11, the measurement under measurement number and the situation of using traditional Puffer type tonometer used under the situation of measuring device 1 number is offset 1.This is to change in order to satisfy the intraocular pressure of determining that is caused by continuous measurement in example 3.
As can be seen from Figure 11, the intraocular pressure in the measure of intraocular pressure of the measuring device 1 in using this embodiment changes follows the measurement of using traditional Puffer type tonometer, thereby obtains identical result basically.
The present inventor finds from above-mentioned example, for the tonometer of the measuring device among this embodiment 1 as repeatable further raising, must measuring device 1 be contacted under the same conditions with people's eyelid for each contact.Yet, when the catalyst 14 of measuring device 1 contacts with the execution measurement with people's eyelid in season, be difficult to the shell 13 of measuring device 1 is placed on people's the eyelid.So as the result of research, the present inventor dreams up provides a kind of supporting base that is used to support the shell 13 of measuring device 1.Figure 12 and 13 illustrates the structure of the measuring device 1 that provides this supporting base.
Shown in Figure 12 and 13, supporting base 23 supports shells 13 and has near the depression profile shape part of the skeletal shape the human eye that approaches wherein.In this embodiment, supporting base 23 is formed and makes left side or the right side of the side shown in Figure 12 corresponding to people's face.In addition, supporting base 23 is formed and makes the left side shown in Figure 13 corresponding to the nasal side relative with eyes, and the right side shown in it is corresponding to the temple side relative with eyes.Therefore, supporting base 23 is configured to support measuring device 1, and near the people covers eyes on the face.When contacting near the depression profile shape of supporting base 23 part and people's the eyeball, catalyst 14 contacts with eyelid 16.In order to prevent that supporting base 23 from influencing measure of intraocular pressure, supporting base 23 is fixed on the outside of shell 13, and it is attached to the part of moving area (the being vibration area) outside that is positioned at catalyst 11 and can not hinders vibration.
Therefore, when the user fixed support pedestal 23 of measuring device 1 so that when measuring intraocular pressure, the hands that user can not occur during vibrating with catalyst 14, the shell 13 that covers vibrator 11 or the contacted situation of similar device.Therefore, use the measurement of measuring device 1 unaffected.Catalyst 14 is relatively fixed to supporting base 23, thereby may makes catalyst 14 under identical condition, contact people's eyelid consistently.
Embodiments of the invention and example thereof have been specifically described above.Yet, the invention is not restricted to the foregoing description, and can carry out various modifications based on technological thought of the present invention.
For example, described in this embodiment numerical value is example, can use different numerical value if necessary.
For example, in the above-described embodiments, adopt the vibrator of bimorph type vibrator as measuring device 1.Can adopt any vibrator that current value wherein changes according to Oscillation Amplitude as this vibrator.For example, can adopt piezo-ceramic vibrators such as Langevin type vibrator.
In the above-described embodiments, be used as the support component of shell 13 internal fixation vibrators 11 as the gum elastic of elasticity entity.Yet, can also use for example spring or synthetic resin.Can also use can be by the fixing other materials of vibrator of suitable power.
In addition, for example in order to produce bigger vibration in the vibrator 11 in the measuring device 1 in the above-described embodiments, can in vibrator 11, further be provided with by pyrite for example, rustless steel or the metal weight of lead (Pb) or copper (Cu) for example.This weight can be arranged in the arbitrary portion of vibrator 11.For the stability of vibrating, wish in the core of vibrator 11, on surface, to be provided with this weight perpendicular to its Oscillation Amplitude direction.
Reference numerals list
1 measuring appliance
2 piezoelectric actuators
3 terminal pedestals
4 information processors
4a operating system
4b information stored data base
The 4c measurement result is processed and is used
4d input data analysis program
The 4e computing is used
4f outlet side frequency shift program
5 resistors
11 vibrators
The 11a ceramic component
The 11b metallic plate
12 rubber earring mouldings
13 shells
14 contactors
15 vibrator cables
16 eyelids
17 eyeballs
21 with reference to pedestal
22 springs
23 supporting bases
Claims (8)
1, a kind of pressure measurement method comprises:
Make vibrating device contact with measured object by contact device, this vibrating device is connected to this contact device so that contact with this measured object and vibrated by applying voltage, and wherein this measured object has predetermined shape and exerts pressure at outward direction from this measured object;
Apply voltage for this vibrating device by voltage bringing device, this voltage bringing device is used for alternating voltage is applied to this vibrating device;
Flow through the current value of this vibrating device by the measuring device measurement, this measuring device is used to measure the current value that flows through this vibrating device; And
Come calculating pressure based on measured current value.
2, pressure measurement method as claimed in claim 1 further comprises:
Based on the variation of the described current value that causes by vibration frequency change, calculate the resonance point of described measured object by information processor; And
Based on the current value that flows through this vibrating device on the frequency field that exists at this resonance point, measure described pressure.
3, a kind of pressure gauge comprises:
Be used for and the contacted contact device of measured object, wherein this measured object has predetermined shape and exerts pressure at outward direction from this measured object;
Vibrating device, it is connected with this contact device and is vibrated by applying voltage;
Voltage bringing device, it is used for applying alternating voltage to this vibrating device;
Measuring device, it is used to measure the current value that flows through this vibrating device; And
Information processor, it is used to calculate the force value corresponding to by the measured current value of this measuring device,
Wherein, when this alternating voltage being applied to this vibrating device this vibrating device contacts by the measured object of this contact device and this simultaneously by this voltage bringing device, flow through this current value of this vibrating device by this measuring device measurement, and calculate the pressure of this measured object by this information processor.
4, pressure gauge as claimed in claim 3, wherein:
Calculate the resonance point of described measured object based on the variation of the measured current value that causes by vibration frequency change; And
The current value of this vibrating device is flow through in measurement on the frequency field that this resonance point exists.
5, as claim 3 or 4 described pressure gauges, further comprise bracing or strutting arrangement,
Wherein, at this bracing or strutting arrangement of outer setting of the moving area of the moving area of described contact device and described vibrating device.
6, a kind of tonometer comprises:
Contact device, it is used for and the eyeball mediate contact;
Vibrating device, it is connected with this contact device and is vibrated by applying voltage;
Voltage bringing device, it is used for applying alternating voltage to this vibrating device;
Measuring device, it is used to measure the current value that flows through this vibrating device; And
Information processor, it is used to calculate the force value corresponding to by this measured current value of this measuring device,
Wherein, when this alternating voltage being applied to this vibrating device this vibrating device contacts with eyeball by this contact device and eyelid simultaneously by this voltage bringing device, flow through this current value of this vibrating device by this measuring device measurement, and calculate the intraocular pressure of eyeball by this information processor.
7, tonometer as claimed in claim 6, wherein:
Calculate the resonance point of described measured object based on the variation of the measured current value that causes by vibration frequency change; And
Measurement on the frequency field that this resonance point exists, flow through this vibrating device current value.
8, as claim 6 or 7 described tonometer, further comprise bracing or strutting arrangement,
Wherein, at this bracing or strutting arrangement of outer setting of the moving area of the moving area of described contact device and described vibrating device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP128423/2004 | 2004-04-23 | ||
| JP2004128423A JP4583801B2 (en) | 2004-04-23 | 2004-04-23 | Pressure measuring method, pressure measuring device and tonometer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101026990A CN101026990A (en) | 2007-08-29 |
| CN100571610C true CN100571610C (en) | 2009-12-23 |
Family
ID=35196685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005800126070A Expired - Fee Related CN100571610C (en) | 2004-04-23 | 2005-03-18 | Pressure measurement method, pressure gauge and tonometer |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US7713197B2 (en) |
| EP (1) | EP1738681A4 (en) |
| JP (1) | JP4583801B2 (en) |
| KR (1) | KR20070004981A (en) |
| CN (1) | CN100571610C (en) |
| RU (1) | RU2372021C2 (en) |
| WO (1) | WO2005102150A1 (en) |
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| DE102006033035B4 (en) * | 2006-07-14 | 2015-06-03 | Universität Bremen | Apparatus and method for contactless internal pressure determination |
| KR100936047B1 (en) | 2008-03-03 | 2010-01-08 | 한국표준과학연구원 | Testing device of an air-buff tonometer |
| IN2012DN03211A (en) * | 2009-09-18 | 2015-10-23 | Orthomems Inc | |
| WO2011035228A1 (en) | 2009-09-18 | 2011-03-24 | Orthomems, Inc. | Implantable mems intraocular pressure sensor devices and methods for glaucoma monitoring |
| KR101114819B1 (en) * | 2010-07-23 | 2012-02-15 | (재)예수병원유지재단 | Contact-type tonometer |
| EP2458357B2 (en) * | 2010-11-29 | 2017-10-18 | Air Products And Chemicals, Inc. | Method of, and Apparatus for, Measuring the Pressure of a Gas |
| KR101233966B1 (en) * | 2011-01-19 | 2013-02-18 | 주식회사 휴비츠 | Method for measuring intraocular pressure |
| KR101329334B1 (en) * | 2012-09-24 | 2013-11-13 | 충남대학교산학협력단 | Apparatus for non-invasive pressure measurement |
| CN103940547A (en) * | 2013-07-17 | 2014-07-23 | 贵州兴化化工股份有限公司 | Decarburization tower pressure testing method |
| JP2015047354A (en) * | 2013-09-02 | 2015-03-16 | セイコーエプソン株式会社 | Ultrasonic measurement apparatus and ultrasonic measurement method |
| CN105919551B (en) * | 2016-04-13 | 2017-07-18 | 华中科技大学 | A kind of non-built-in mode detection of eyeball tension sensor based on micro-fluidic technologies |
| WO2018031386A1 (en) * | 2016-08-09 | 2018-02-15 | Li Zan | Portable devices for monitoring eye diseases and methods thereof |
| CN106725298B (en) * | 2017-03-05 | 2019-04-30 | 苏州云目医疗技术有限公司 | A kind of movement mechanism, intraocular pressure measurement pressure probe and tonometer |
| US20210068656A1 (en) * | 2018-03-30 | 2021-03-11 | Nidek Co., Ltd. | Non-contact ultrasonic ophthalmotonometer |
| JP7110680B2 (en) * | 2018-03-30 | 2022-08-02 | 株式会社ニデック | non-contact ultrasonic tonometer |
| JP7110681B2 (en) * | 2018-03-30 | 2022-08-02 | 株式会社ニデック | non-contact ultrasonic tonometer |
| CN109793496A (en) * | 2018-12-04 | 2019-05-24 | 苏州大学 | A kind of device and the application of combination sensor and SS-OCT technical testing intraocular pressure |
| JP7259599B2 (en) * | 2019-07-03 | 2023-04-18 | 株式会社ニデック | ultrasonic tonometer |
| WO2022031096A1 (en) * | 2020-08-07 | 2022-02-10 | 한양대학교 산학협력단 | Device and method for measuring intraocular pressure |
| KR102531033B1 (en) * | 2020-08-07 | 2023-05-11 | 한양대학교 산학협력단 | Apparatus and method for measuring intraocular pressure |
| CN113866544B (en) * | 2021-09-29 | 2023-05-30 | 中国科学院光电技术研究所 | Device for measuring displacement output under load of piezoelectric ceramic driver |
| CN113884231B (en) * | 2021-09-29 | 2023-05-30 | 中国科学院光电技术研究所 | Device for testing output force of piezoelectric ceramic driver |
| UA150315U (en) * | 2021-11-18 | 2022-01-26 | Дмитро Вікторович Вакуленко | Automatic tonometer |
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- 2005-03-18 KR KR1020067024453A patent/KR20070004981A/en active IP Right Grant
- 2005-03-18 CN CNB2005800126070A patent/CN100571610C/en not_active Expired - Fee Related
- 2005-03-18 WO PCT/JP2005/004916 patent/WO2005102150A1/en active Application Filing
- 2005-03-18 RU RU2006141351/14A patent/RU2372021C2/en not_active IP Right Cessation
- 2005-03-18 EP EP05721103A patent/EP1738681A4/en not_active Withdrawn
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| US4646754A (en) * | 1985-02-19 | 1987-03-03 | Seale Joseph B | Non-invasive determination of mechanical characteristics in the body |
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Also Published As
| Publication number | Publication date |
|---|---|
| CN101026990A (en) | 2007-08-29 |
| EP1738681A1 (en) | 2007-01-03 |
| JP4583801B2 (en) | 2010-11-17 |
| EP1738681A4 (en) | 2009-07-29 |
| JP2005304930A (en) | 2005-11-04 |
| US7713197B2 (en) | 2010-05-11 |
| RU2006141351A (en) | 2008-05-27 |
| KR20070004981A (en) | 2007-01-09 |
| US20070197893A1 (en) | 2007-08-23 |
| WO2005102150A1 (en) | 2005-11-03 |
| RU2372021C2 (en) | 2009-11-10 |
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